diff options
| author | rpj <rpj> | 2004-10-01 07:17:09 +0000 |
|---|---|---|
| committer | rpj <rpj> | 2004-10-01 07:17:09 +0000 |
| commit | b0cf9efa6afeb8a7dbddf124dae173a2d633c801 (patch) | |
| tree | 8f208f15bd63cf69ae9e2ceb2d523296db8bca76 /ChangeLog | |
| parent | 531ca4db4794aab863a898b4d079ccd59b424b25 (diff) | |
Mutex speedups
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 42 |
1 files changed, 29 insertions, 13 deletions
@@ -1,23 +1,39 @@ +2004-09-27 Ross Johnson <rpj at callisto.canberra.edu.au>
+ + * pthread_mutex_lock.c (pthread_mutex_lock): Separate PTHREAD_MUTEX_NORMAL
+ logic since we do not need to keep or check some state required by other
+ mutex types; do not check mutex pointer arg for validity - leave this to
+ the system since we are only checking for NULL pointers. This should improve
+ speed of NORMAL mutexes and marginally improve speed of other type.
+ * pthread_mutex_trylock.c (pthread_mutex_trylock): Likewise.
+ * pthread_mutex_unlock.c (pthread_mutex_unlock): Likewise; also avoid
+ entering the critical section for the no-waiters case, with approx. 30%
+ reduction in lock/unlock overhead for this case..
+ * pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise; also
+ no longer keeps mutex if post-timeout second attempt succeeds - this will
+ assist applications that wish to impose strict lock deadlines, rather than
+ simply to escape from frozen locks.
+ 2004-09-09 Tristan Savatier <tristan at mpegtv.com>
- * pthread.h (struct pthread_once_t_): Qualify the 'done' element - as 'volatile'. - * pthread_once.c: Concerned about possible race condition, - specifically on MPU systems re concurrent access to multibyte types. - [Maintainer's note: the race condition is harmless on SPU systems - and only a problem on MPU systems if concurrent access results in an - exception (presumably generated by a hardware interrupt). There are - other instances of similar harmless race conditions that have not been - identified as issues.] + * pthread.h (struct pthread_once_t_): Qualify the 'done' element
+ as 'volatile'.
+ * pthread_once.c: Concerned about possible race condition,
+ specifically on MPU systems re concurrent access to multibyte types.
+ [Maintainer's note: the race condition is harmless on SPU systems
+ and only a problem on MPU systems if concurrent access results in an
+ exception (presumably generated by a hardware interrupt). There are
+ other instances of similar harmless race conditions that have not been
+ identified as issues.]
2004-09-09 Ross Johnson <rpj at callisto.canberra.edu.au>
- * pthread.h: Declare additional types as volatile. + * pthread.h: Declare additional types as volatile.
2004-08-27 Ross Johnson <rpj at callisto.canberra.edu.au>
- * pthread_barrier_wait.c (pthread_barrier_wait): Remove excessive code - by substituting the internal non-cancelable version of sem_wait - (ptw32_semwait). + * pthread_barrier_wait.c (pthread_barrier_wait): Remove excessive code
+ by substituting the internal non-cancelable version of sem_wait
+ (ptw32_semwait).
2004-08-25 Ross Johnson <rpj at callisto.canberra.edu.au>
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